The 404 was introduced on the 30th November 1996 and provided a Monday to Saturday service between Coulsdon Red Lion & Caterham On The Hill Westway common. London & Country buses operated the 404 from their Croydon Depot using Midi Buses. The current PVR was 1Midi Monday to Saturday. On the 25th July 1998, the route was passed to Metrobus on a short term emergency contract, due to the surrender of London & Country, still using the midi buses. A month later on the 29th August, the route was diverted to serve Stoneyfield Road & Marpit Lane. A month after the route being revised Quality Line also known as Epsom buses gained the contract for the 404 using the Midi’s.

A couple of years on the loop working in the Caterham area was withdrawn with buses now going direct through Westway common. On the 27th September 2003 Quality Line retained the contract for the 404 using a solo bus. The PVR stayed the same as 1Solo Monday to Saturday. Five years later on the 27th September 2008 Quality Line yet again retained the contract for the 404, using their solos. On the 28th September 2013 this year Quality retained the contract for the 404, using a new bus which is yet to be confirmed. The average journey time is between 24-27mins. The frequency Monday to Saturday is 1 bus every hour.